Does anyone know if there is a long range RFID sensor available or something I could convert to do long range?

I'm looking into an idea for tracking animals. I'm thinking if I can get a long range RFID reader, I can get a general direction. Once the signal is strong enough, switch to a medium range reader, then a short range reader. The idea being that I can get at least relatively close to the area the animal would be. I don't know much about RFID yet, however.

If RFID won't work, does anyone have any suggestions of what might work?

Looking at http://www.parallax.com/product/28140 looks like this won't be strong enough to detect an animals RFID.

Electronic Technician, Electronic Engineering Technician
I love to build things. Test equipment, replica and original sci fi props and costume pieces, and whatever else I feel like at the time. I have an Ultimaker and a 3D engraver. I rarely put a kit tog

"Near field UHF RFID tags contain a small silicon chip and an antenna paired onto or into an object. This allows one to create tags which can be read from inches to 10s of feet in a passive configuration, and 100s to 1000s of feet if used semi-passively (the tag still changes the RF that comes back to the reader rather than transmitting, but gets a battery to help it out) or actively (an active transmitter)."

Electronic Technician, Electronic Engineering Technician
I love to build things. Test equipment, replica and original sci fi props and costume pieces, and whatever else I feel like at the time. I have an Ultimaker and a 3D engraver. I rarely put a kit tog

I might as well state my idea here so you get an idea of what I'm trying to do. I was looking at creating a quadcopter that would follow / track an RFID tag and potentially report its position to my phone. So the distance could be pretty far or relatively close. I suppose I'm looking for max possible. I have been somewhat distracted with another idea at the moment, but maybe if this is viable for me I may come back to it

Electronic Technician, Electronic Engineering Technician
I love to build things. Test equipment, replica and original sci fi props and costume pieces, and whatever else I feel like at the time. I have an Ultimaker and a 3D engraver. I rarely put a kit tog

There are a few trade-off scenarios we should work through. First, how high do you want the quadcopter to fly? Also, is the goal of the quadcopter to locate the animal(s) or simply report what was scanned during a flyby? (i.e., if a rancher wants to locate the position of an animal the quad would need to sweep the land until the animal was found; but, if you wanted to sample the population of a wildlife refuge, you might want to set a flight path and merely report which animals were present). Each scenario may have a trade-off based on the flight time available vs the distance needing to be scanned at once. So, to stay true to my previous examples, if you were locating an animal then you would need to sweep the land (much like a Roomba). The number of sweeps would need to be compared to the range of the RFID scanner.

With that said, I don't think you will have any credible choice other than using an active UHF RFID tag to extend the range. According to wikipeida, the range of an active UHF tag is 100 meters but that probably assumes that the reader is fixed and you need to have a mobile reader. It might be possible to create an array of fixed readers/antennas to create a long range mobile reader...

The key point with RFID is that it is possible to work with devices that have no battery. The device gets enough power from the reader device, and that limits the range to centimetres not metres [ unless you are allowed to blast the whole vicinity with high-powered transmissions from your RFID reader ].

A device that has a GPS chip and also a GSM transmitter obviously has a battery. If you are able to attach a big enough device to an animal for that to work, you don't need RFID.

I am a biologist, visual artist, and educator working with the Ecotarium in Massachusetts. I help create interactive exhibits that connect children in urban areas with the wildlife that thrive in cities.

Hello!I was hoping to revive this thread and take it on a tangent. I am also working to use long range UHF RFD to track wildlife, but in this case wild turkeys. I am working with a science museum on projects to connect people with urban wildlife and we want to gather data on turkeys that live on the property using an array of readers.

Does any one have advice about how to best find a suitable tag for a turkey? I was hoping there might just be a larger version of those I have seen for songbirds.

Also, I was hoping someone could fill me in on how things would change if I needed to track more than one bird simultaneously.